Revert "pylint: upgrade to 1.3.1"

third_party/logilab/astroid/protocols.py

-# copyright 2003-2013 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
-# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
-#
-# This file is part of astroid.
-#
-# astroid is free software: you can redistribute it and/or modify it
-# under the terms of the GNU Lesser General Public License as published by the
-# Free Software Foundation, either version 2.1 of the License, or (at your
-# option) any later version.
-#
-# astroid is distributed in the hope that it will be useful, but
-# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
-# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
-# for more details.
-#
-# You should have received a copy of the GNU Lesser General Public License along
-# with astroid. If not, see <http://www.gnu.org/licenses/>.
-"""this module contains a set of functions to handle python protocols for nodes
-where it makes sense.
-"""
-
-__doctype__ = "restructuredtext en"
-
-from astroid.exceptions import InferenceError, NoDefault, NotFoundError
-from astroid.node_classes import unpack_infer
-from astroid.bases import copy_context, \
-     raise_if_nothing_infered, yes_if_nothing_infered, Instance, YES
-from astroid.nodes import const_factory
-from astroid import nodes
-
-BIN_OP_METHOD = {'+':  '__add__',
-                 '-':  '__sub__',
-                 '/':  '__div__',
-                 '//': '__floordiv__',
-                 '*':  '__mul__',
-                 '**': '__power__',
-                 '%':  '__mod__',
-                 '&':  '__and__',
-                 '|':  '__or__',
-                 '^':  '__xor__',
-                 '<<': '__lshift__',
-                 '>>': '__rshift__',
-                }
-
-UNARY_OP_METHOD = {'+': '__pos__',
-                   '-': '__neg__',
-                   '~': '__invert__',
-                   'not': None, # XXX not '__nonzero__'
-                  }
-
-# unary operations ############################################################
-
-def tl_infer_unary_op(self, operator):
-    if operator == 'not':
-        return const_factory(not bool(self.elts))
-    raise TypeError() # XXX log unsupported operation
-nodes.Tuple.infer_unary_op = tl_infer_unary_op
-nodes.List.infer_unary_op = tl_infer_unary_op
-
-
-def dict_infer_unary_op(self, operator):
-    if operator == 'not':
-        return const_factory(not bool(self.items))
-    raise TypeError() # XXX log unsupported operation
-nodes.Dict.infer_unary_op = dict_infer_unary_op
-
-
-def const_infer_unary_op(self, operator):
-    if operator == 'not':
-        return const_factory(not self.value)
-    # XXX log potentially raised TypeError
-    elif operator == '+':
-        return const_factory(+self.value)
-    else: # operator == '-':
-        return const_factory(-self.value)
-nodes.Const.infer_unary_op = const_infer_unary_op
-
-
-# binary operations ###########################################################
-
-BIN_OP_IMPL = {'+':  lambda a, b: a + b,
-               '-':  lambda a, b: a - b,
-               '/':  lambda a, b: a / b,
-               '//': lambda a, b: a // b,
-               '*':  lambda a, b: a * b,
-               '**': lambda a, b: a ** b,
-               '%':  lambda a, b: a % b,
-               '&':  lambda a, b: a & b,
-               '|':  lambda a, b: a | b,
-               '^':  lambda a, b: a ^ b,
-               '<<': lambda a, b: a << b,
-               '>>': lambda a, b: a >> b,
-              }
-for key, impl in BIN_OP_IMPL.items():
-    BIN_OP_IMPL[key+'='] = impl
-
-def const_infer_binary_op(self, operator, other, context):
-    for other in other.infer(context):
-        if isinstance(other, nodes.Const):
-            try:
-                impl = BIN_OP_IMPL[operator]
-
-                try:
-                    yield const_factory(impl(self.value, other.value))
-                except Exception:
-                    # ArithmeticError is not enough: float >> float is a TypeError
-                    # TODO : let pylint know about the problem
-                    pass
-            except TypeError:
-                # XXX log TypeError
-                continue
-        elif other is YES:
-            yield other
-        else:
-            try:
-                for val in other.infer_binary_op(operator, self, context):
-                    yield val
-            except AttributeError:
-                yield YES
-nodes.Const.infer_binary_op = yes_if_nothing_infered(const_infer_binary_op)
-
-
-def tl_infer_binary_op(self, operator, other, context):
-    for other in other.infer(context):
-        if isinstance(other, self.__class__) and operator == '+':
-            node = self.__class__()
-            elts = [n for elt in self.elts for n in elt.infer(context)
-                    if not n is YES]
-            elts += [n for elt in other.elts for n in elt.infer(context)
-                     if not n is YES]
-            node.elts = elts
-            yield node
-        elif isinstance(other, nodes.Const) and operator == '*':
-            if not isinstance(other.value, int):
-                yield YES
-                continue
-            node = self.__class__()
-            elts = [n for elt in self.elts for n in elt.infer(context)
-                    if not n is YES] * other.value
-            node.elts = elts
-            yield node
-        elif isinstance(other, Instance) and not isinstance(other, nodes.Const):
-            yield YES
-    # XXX else log TypeError
-nodes.Tuple.infer_binary_op = yes_if_nothing_infered(tl_infer_binary_op)
-nodes.List.infer_binary_op = yes_if_nothing_infered(tl_infer_binary_op)
-
-
-def dict_infer_binary_op(self, operator, other, context):
-    for other in other.infer(context):
-        if isinstance(other, Instance) and isinstance(other._proxied, nodes.Class):
-            yield YES
-        # XXX else log TypeError
-nodes.Dict.infer_binary_op = yes_if_nothing_infered(dict_infer_binary_op)
-
-def instance_infer_binary_op(self, operator, other, context):
-    try:
-        methods = self.getattr(BIN_OP_METHOD[operator])
-    except (NotFoundError, KeyError):
-        # Unknown operator
-        yield YES
-    else:
-        for method in methods:
-            if not isinstance(method, nodes.Function):
-                continue
-            for result in method.infer_call_result(self, context):
-                if result is not YES:
-                    yield result
-            # We are interested only in the first infered method,
-            # don't go looking in the rest of the methods of the ancestors.
-            break
-
-Instance.infer_binary_op = yes_if_nothing_infered(instance_infer_binary_op)
-
-
-# assignment ##################################################################
-
-"""the assigned_stmts method is responsible to return the assigned statement
-(e.g. not inferred) according to the assignment type.
-
-The `asspath` argument is used to record the lhs path of the original node.
-For instance if we want assigned statements for 'c' in 'a, (b,c)', asspath
-will be [1, 1] once arrived to the Assign node.
-
-The `context` argument is the current inference context which should be given
-to any intermediary inference necessary.
-"""
-
-def _resolve_looppart(parts, asspath, context):
-    """recursive function to resolve multiple assignments on loops"""
-    asspath = asspath[:]
-    index = asspath.pop(0)
-    for part in parts:
-        if part is YES:
-            continue
-        # XXX handle __iter__ and log potentially detected errors
-        if not hasattr(part, 'itered'):
-            continue
-        try:
-            itered = part.itered()
-        except TypeError:
-            continue # XXX log error
-        for stmt in itered:
-            try:
-                assigned = stmt.getitem(index, context)
-            except (AttributeError, IndexError):
-                continue
-            except TypeError: # stmt is unsubscriptable Const
-                continue
-            if not asspath:
-                # we achieved to resolved the assignment path,
-                # don't infer the last part
-                yield assigned
-            elif assigned is YES:
-                break
-            else:
-                # we are not yet on the last part of the path
-                # search on each possibly inferred value
-                try:
-                    for infered in _resolve_looppart(assigned.infer(context),
-                                                     asspath, context):
-                        yield infered
-                except InferenceError:
-                    break
-
-
-def for_assigned_stmts(self, node, context=None, asspath=None):
-    if asspath is None:
-        for lst in self.iter.infer(context):
-            if isinstance(lst, (nodes.Tuple, nodes.List)):
-                for item in lst.elts:
-                    yield item
-    else:
-        for infered in _resolve_looppart(self.iter.infer(context),
-                                         asspath, context):
-            yield infered
-
-nodes.For.assigned_stmts = raise_if_nothing_infered(for_assigned_stmts)
-nodes.Comprehension.assigned_stmts = raise_if_nothing_infered(for_assigned_stmts)
-
-
-def mulass_assigned_stmts(self, node, context=None, asspath=None):
-    if asspath is None:
-        asspath = []
-    asspath.insert(0, self.elts.index(node))
-    return self.parent.assigned_stmts(self, context, asspath)
-nodes.Tuple.assigned_stmts = mulass_assigned_stmts
-nodes.List.assigned_stmts = mulass_assigned_stmts
-
-
-def assend_assigned_stmts(self, context=None):
-    return self.parent.assigned_stmts(self, context=context)
-nodes.AssName.assigned_stmts = assend_assigned_stmts
-nodes.AssAttr.assigned_stmts = assend_assigned_stmts
-
-
-def _arguments_infer_argname(self, name, context):
-    # arguments information may be missing, in which case we can't do anything
-    # more
-    if not (self.args or self.vararg or self.kwarg):
-        yield YES
-        return
-    # first argument of instance/class method
-    if self.args and getattr(self.args[0], 'name', None) == name:
-        functype = self.parent.type
-        if functype == 'method':
-            yield Instance(self.parent.parent.frame())
-            return
-        if functype == 'classmethod':
-            yield self.parent.parent.frame()
-            return
-    if name == self.vararg:
-        vararg = const_factory(())
-        vararg.parent = self
-        yield vararg
-        return
-    if name == self.kwarg:
-        kwarg = const_factory({})
-        kwarg.parent = self
-        yield kwarg
-        return
-    # if there is a default value, yield it. And then yield YES to reflect
-    # we can't guess given argument value
-    try:
-        context = copy_context(context)
-        for infered in self.default_value(name).infer(context):
-            yield infered
-        yield YES
-    except NoDefault:
-        yield YES
-
-
-def arguments_assigned_stmts(self, node, context, asspath=None):
-    if context.callcontext:
-        # reset call context/name
-        callcontext = context.callcontext
-        context = copy_context(context)
-        context.callcontext = None
-        for infered in callcontext.infer_argument(self.parent, node.name, context):
-            yield infered
-        return
-    for infered in _arguments_infer_argname(self, node.name, context):
-        yield infered
-nodes.Arguments.assigned_stmts = arguments_assigned_stmts
-
-
-def assign_assigned_stmts(self, node, context=None, asspath=None):
-    if not asspath:
-        yield self.value
-        return
-    for infered in _resolve_asspart(self.value.infer(context), asspath, context):
-        yield infered
-nodes.Assign.assigned_stmts = raise_if_nothing_infered(assign_assigned_stmts)
-nodes.AugAssign.assigned_stmts = raise_if_nothing_infered(assign_assigned_stmts)
-
-
-def _resolve_asspart(parts, asspath, context):
-    """recursive function to resolve multiple assignments"""
-    asspath = asspath[:]
-    index = asspath.pop(0)
-    for part in parts:
-        if hasattr(part, 'getitem'):
-            try:
-                assigned = part.getitem(index, context)
-            # XXX raise a specific exception to avoid potential hiding of
-            # unexpected exception ?
-            except (TypeError, IndexError):
-                return
-            if not asspath:
-                # we achieved to resolved the assignment path, don't infer the
-                # last part
-                yield assigned
-            elif assigned is YES:
-                return
-            else:
-                # we are not yet on the last part of the path search on each
-                # possibly inferred value
-                try:
-                    for infered in _resolve_asspart(assigned.infer(context),
-                                                    asspath, context):
-                        yield infered
-                except InferenceError:
-                    return
-
-
-def excepthandler_assigned_stmts(self, node, context=None, asspath=None):
-    for assigned in unpack_infer(self.type):
-        if isinstance(assigned, nodes.Class):
-            assigned = Instance(assigned)
-        yield assigned
-nodes.ExceptHandler.assigned_stmts = raise_if_nothing_infered(excepthandler_assigned_stmts)
-
-
-def with_assigned_stmts(self, node, context=None, asspath=None):
-    if asspath is None:
-        for _, vars in self.items:
-            if vars is None:
-                continue
-            for lst in vars.infer(context):
-                if isinstance(lst, (nodes.Tuple, nodes.List)):
-                    for item in lst.nodes:
-                        yield item
-nodes.With.assigned_stmts = raise_if_nothing_infered(with_assigned_stmts)
-
-